Over the past couple of months I have used the body scan machine in the gym. You know that expensive machine near (or in) the changing room that gives you a full body reading of your body fat percentage, BMI and everything else. Over the past month, I have seen my belly get flatter and flatter.
I have seen my arms and my back muscles get more defined. But for some reason, the reading of my body fat percentage won’t fall below 24%. Yet if I use my scales at home I get a reading of 22.8% and if I use the skinfold calipers I get a reading of 22%. This seems a lot more accurate!
Why are these machines so inaccurate?
So these machines send small electrical pulses through your body. They are so small in fact you can’t even feel them. These pulses measure your body fat and muscle mass by looking at the amount of resistance the pulses have to cope with – mainly from fatty tissues.
The reason fat cells offer more resistance than muscle mass is because fat cells contain very little water content. Muscles however contain a larger proportion of water which, as many of you already know, is a great conductor of electricity.
These machines are great if you have no idea what kind of body fat % you have. If you are like myself and you know your body fat percentage, your muscle mass and everything else then they really aren’t much use.
I have seen my muscles increase and decrease week on week without much reason. I have seen my muscle mass drop by 2kg on these machines, when the reality is I’m putting on muscle.
Last week for example, I lost 1kg (2.2lbs) of body weight. I was working out and maintaining a high protein diet. I was getting stronger. But according to the machine I had lost 2kg of muscle mass and put on 1kg of fat mass.
How is that possible?! Well it is… but it’s highly unlikely!
When to use the machines efficiently
To use these machines efficiently, you would have to use it once a month. Maybe even less if you want a general understanding of your body and your progress.
If you want a more accurate way of tracking your body fat percentages I would recommend getting yourself a skinfold caliper. There are plenty of tutorials on YouTube explaining how to use them.
If you have a personal trainer, they should be able to perform a body fat reading on you as well.